A carrier conversion would also require larger yards and bases

If a Queen Elizabeth-class carrier were lengthened, where could the work be done and where could the larger ship be based?

Cammell Laird is the likely yard, but its dry dock and the carrier's British base facilities would all require costly expansion.

The conversion question extends beyond naval architecture to the industrial facilities capable of splitting and rejoining a carrier hull. Cammell Laird is identified as the British yard capable of that work, though its dock would need enlargement. Domestic procurement is judged more likely than an overseas option, and Plymouth and Portsmouth would also need substantial investment. The blank cheque for CATOBAR conversion would therefore cover shipyard and basing infrastructure as well as the ship and aircraft themselves.